谁若不能独立，谁就谈不上自由。
数学是为不同事物赋予相同名称的艺术。
Will you wilt under criticism， or will you follow your convictions？
The act of writing is an act of optimism. You would not take the trouble to do it if you felt it didn't matter.
避免错误的最佳方式是积累经验。